All references cited in this specification, and their references, are incorporated by reference herein where appropriate for teachings of additional or alternative details, features and/or technical background.
Disclosed is image sensor module architecture related to imaging devices in general and to compact scanners in particular.
Known image sensor module architectures have limitations, such as large dimensions, not being able to accommodate higher intensity document illuminators and excessive assembly and disassembly times. These aspects can be overcome through architectural alterations which are described herein.
FIG. 1a illustrates a cross section of a typical common image sensing module 20 positioned underneath a glass platen 10 of a scanner. Image sensing module 20 includes a light source 45, optical system 33 and an image sensor (not shown) on circuit board 80. A document handler 15 feeds a document 5 over the platen. As the document passes over image sensing module 20, the document is illuminated by light source 45, through aperture 35 guided by illuminator 40. Illuminators 40 are housed in housing 50. The light reflected by document 5 is then focused through optical path 30 by optical lens system 33 onto image sensors. Image sensors, such as charge coupled devices (CCDs), typically have a row or linear array of photosensors with suitable supporting circuitry integrated onto a circuit board 80. When the document moves past the linear array, each of the photosensors converts reflected light from the original image into electrical signals, which in turn can be converted into digital data.
A perspective view of the image sensing module 20 is also shown in FIG. 1b with similar numerals referring to similar parts of FIG. 1a. As is seen in both Figures, circuit board 80 is mounted onto the body 60 of module 20 by means of fasteners, such as screws 90. The circuit board is offset from the body of the module with standoffs by an amount to accommodate other components, such as a connector in the middle, thus increasing the overall height h of the module. Furthermore, the overall width, w, of the module is governed by the width of the individual low-profile illuminators 40. It is often difficult to make the illuminators laterally short enough to fit within the limited space of compact scanners having a short focal distance along the optical path 30. In addition, it is known that the present image sensor modules are configured to be positioned at a fixed position for a specified platen glass thickness, t, as shown in FIG. 1a. 
In order to satisfy the needs for even more compact and more powerful scanners, it is desirable to reduce the over-all dimensions of the image sensor modules while at the same time providing even larger illuminators for enhanced luminescence in scanning a document. It is also desirable to allow for the illuminators to be fully adjustable for optimum performance for any platen glass thickness, or for no glass at all. Further, improved fasteners for quick assembly and disassembly of the circuit board and supporting electronics boards would also improve the overall architecture of the image sensor module system.